The publisher recently partnered with a design and development company called ScrollMotion to launch a series of bestselling in-copyright e-books for the iPhone where each title is its own app and a reader is bundled with each download. Thus the iPhone itself, despite the small screen and lack of E Ink technology, becomes the reader.

On the other side, the recently released Classics app uses the iPhone’s software update to load new ebooks, and a number of publishers (including O’Reilly) deliver ebooks to the iPhone and iPod Touch through the Stanza e-reader.

Both methods have their pros and cons (e.g. storage limitations, selection, interface), but I’d like to know what TOC readers think: Which format holds the most promise? Which do you use?